{"instruction": "You are an expert in named entity recognition. Please extract entities that match the schema definition from the input. Return an empty list if the entity type does not exist. Please respond in the format of a JSON string.", "schema": ["protein", "RNA", "cell type", "cell line", "DNA"], "input": "After the DNA fragment containing the CAG repeats is amplified by the polymerase chain reaction , a primer extension is carried out; the extension of the end-labelled reverse primer adjacent to 3' end of CAG repeats stops at the first T after CAG repeats with the incorporation of dideoxy ATP in the reaction mixture."}
{"protein": [], "RNA": [], "cell type": [], "cell line": [], "DNA": ["DNA fragment", "CAG repeats", "end-labelled reverse primer", "3' end"]}